The present invention relates, in general, to a guide rail for the valve train of an internal combustion engine.
Guide rails are used in internal combustion engines for preventing rotations of valve lifters that are configured as roller lifters. In addition, guide rails serve as installation aid and may be used in particular for the roller lifters of a pushrod valve train. German patent publication DE 197 12 610 A1 describes a guide rail for an internal combustion engine of a type having receiving sockets spaced along the length thereof for accommodating valve lifters. The valve lifters, typically roller valve lifters, are in engagement with cam lobes of a camshaft. As the lifters must not rotate about its longitudinal axis, because the roller on the lifter must remain in the same plane as the cam lobe, the lifters are suitably aligned in the cylinder block of the internal combustion engine by particular retainers and restrained against rotation.
Roller lifters for certain motors with V-shaped arrangement of the cylinders are widened in a trumpet-shaped manner at the contact area of the pushrod, because the pushrod would otherwise contact the associated springy support sheet as a consequence of its tilt angle in relation to the longitudinal lifter axis.
It would therefore be desirable and advantageous to provide an improved guide rail to prevent such a contact and to construct it to allow valve lifters, which are widened in trumpet-shaped manner, to be installed and retained in a simple manner while yet being reliable in operation.